A wireless communications provider can implement one or more home service areas in which the wireless communications provider communicates directly with one or more wireless communication devices (also referred to as mobile devices or mobile handsets). Subscribers (or subscriber devices) receive service directly from the wireless communications provider when they are within the footprint of any of the home service areas. For example, a wireless communications provider can implement a service area encompassing San Diego, Calif. Subscribers of the wireless communications provider thus can be considered to be on the home network when located within the San Diego service area.
A subscriber who is located outside of a home service area is generally referred to as roaming. The wireless communications provider can cooperate with one or more third-party service providers to permit its subscribers to access wireless communications services when they are roaming. For example, the wireless communications provider can establish service agreements with one or more third-party service providers (or roaming partners), including reciprocal service agreements. Typically, a roaming subscriber is charged additional fees in exchange for accessing wireless communications service through a third-party service provider, such as connection charges and additional air-time fees. Further, one or more services available to a subscriber through the home network may not be available to the subscriber when roaming, such as access to account information.
In order to access wireless communications services, such as placing outgoing telephone calls, receiving incoming telephone calls, and transmitting/receiving electronic messages, a roaming subscriber must register with the third-party service provider operating the network in which the subscriber is roaming. One or more details regarding the roaming subscriber can be written into a Visitor Location Register (VLR) maintained by the third-party service provider, such as when the roaming subscriber enters the third-party service area. The information stored in the VLR can be collected through messaging with the Home Location Register (HLR) corresponding to the subscriber. Further, the messaging can be performed in accordance with an established messaging protocol, such as SS7. For example, the VLR can store the subscriber's identity, such as from a subscriber identity module, authentication data, the subscriber's telephone number, and the address of the HLR corresponding to the subscriber. The VLR can then communicate with the HLR to determine whether and what types of service can be provided to the roaming subscriber. Once the roaming subscriber leaves a particular service area, the information associated with the roaming subscriber can be deleted from the VLR.